Button-hole sewing-machine



2 Sheets-,Sheet 1.

(No Model.)

A. L. COOMBS. BUTTON HOLE SEWING'MAGHINB.

Patented sept. 18, 1888.

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N. PETERS. Fhulu-Liumgmpher. wnningmn, D. C.

(Nomaden) y 8 sheets-sheen 2'.

l ANL. GOUMBS. BUTTON EoLE SEWING MACHINE.

Y No. 889,547. 128881188888188. 18, 1888-'.

Zass. jnwn 07:/ Mfg@ f @hawk/66m@ UNITED STATES PATENT OFFICE.

A. LINCOLN COOMBS, OF. CLIFTONDALE, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TC THE SINGER MANUFACTURING COMPANY OF NEW JERSEY.

BUTTON-HOLE SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 389,547, dated September 18, 1888.

Application filed January 16, 1886. Serial'No. 188,745. (No model.)

To @ZZ whom it may concern.-

Be it known that I, A. LINCOLN CooMEs,of Cliftondale,county of Essex, and State of Massachusetts,lhave invented an improvement in Sewing-Machines, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention has for its object to improve 1o that class of button-hole-stitching machines wherein the cloth or other material is carried by a clamp, and the needle-bar, besides reciprocating, is moved laterally to penetrate the material back of the edge of the slit to be I5 stitched and then to descend over the edge, my improvements consisting in providing such class of machines with means whereby the clothelamp may be automatically vibrated as the small end of the button-hole slit is reaehedsto be zo finished, such vibration of the clamp, coupled with the usual motion of the needle, enabling the small end of the slit to be barred,77 as it is called, by stitches extended from outside to outside of the stitching covering the side edges z 5 of the button-hole slit, and, the barring completed,the machine is automatically stopped.

My invention is herein embodied in connection with a machinehaving stitch-forming and cloth-clamp-moving scrolls, substantially such 3o as represented in United States Patent No. 123,348, dated February 6, 1872, to which reference may be had.

In accordance with my invention the machine below the bed-plate is provided with a vibrating lever having jointed to it a pawlcarrying slide, upon which is pivotcd a pawl which is acted upon by a spring, the normal tendency of the spring being to cause the pawl to engage the teeth of a holding-bar and move it to release a pivotcd lever,upon which is mounted a rotating belt-wheel, and let'it drop from contact with a friction-pulley fast on the main shaft. The pawl carrying slide is loosely connected with a slide-bar, one end of which is extended upward through a hole in the bed-plate and placed in such position as to co-operate with a normally-extended arm attached rigidly to the cloth-clamp, the said arm being brought within the range of movement of the said slide-bar as the last side of 5o the button-hole slitis stitched to its end ready to be barred. The inner end ofthis slide-bar has a finger which controls the time of engagement of the pawl referred to with the holding-bar referred to. The slide-bar is reeiprocated uniformly by the vibrating lever while both sides of the slit and its large end are being overstitched; but as soon as the arm of the clamp comes within the range of movement of the slide-bar the latter acts upon the said arm and vibrates the clamp, as will be described, to enable the barring to be done, the number of stitches in the bar being controlled by the number of teeth in the holdingbar, to be described.

The particular features in which my invention consist will be herein described, and spe- 'ciically pointed out in the claims at the end of this specification.

Figure 1 is a plan view of the bed-plate of a sewing-machine of the kind referred to, the said figure showing the base part of the usual cloth-clamp with my improved arm attached to it, the ligure also showing` the devices added by me to vibrate the said clamp, as described, and to operate the releasing-bar, the bed-plate being partially broken out to better show some of the devices below it. Fig. '2 is a section of Fig. 1 in the dotted line a: x. Fig. 3 is a rear end View of a sewing-machine provided with my improvements, to show the driving meehanism employed with it, said driving mechanism not,however,being ofmy invention. Fig. 4 is an under side View of the slide-bar, the pawlcarrying slide, the pawl, and part of the lever for moving the same; and Fig. 5 is an under side view of the clamp-base.

The bed-plate A, the upright arm A', the main shaft A3, the friction-pulley A4 thereon, the lever D, having the hub 5, the belt-pulley A5, mounted on the said hub, the stud D", held by the yoke D', and the upright shaft A2, driven from the main shaft A3 by bevelgears on each, are shown in Fig. 3; but as the said devices are not of my invention they need not be therein specifically described. The shaft A2 has fast to it at its lower end the cam C2.

The bed-plate A, the cover B, provided with the slot ll to receive the pin 2, carried bythe base of the clamp C, and the two scrollcams B2 l" are common to the patent rcferred to.

TheleverDsee Fig.3,)hasat oneenda foot, Dl, made as a screw,'and therefore adjustable with relation to the said lever, the said foot being adapted to bear upon a holding-bar, 44, kept pressed toward the said holding-bar by a spring, 53.

The lever b, pivoted to the under side of the bedplate at b", has a central opening within which acts the cam Cl, secured to the lower end ofthe upright shaft Al, and vibrates the said lever continuously. The lever blhas pivoted to its forward end the pawl-carrying slide bl, the outer end of which is flanged or turned up to form three sides of a box and constitute a guide, b, for the reception of the inner end of the slide-bar cl, the latter having a slot, c3, which is entered by a screw, c. The paw1carrier has a pawl, bl, pivoted upon it at 12, and a spring, 13, acts on the back of the pawl. The pawl-earrier has a lug, 14, in which is placed an adjusting-screw, 15, the turning of the said screw in or out altering the length of the effective stroke of the said slidebar to accommodate for the length of the barstitch to be made, that depending upon the size of the button-hole and the class of work being done, the end of the said adj nstingscrew acting directly against the end of the said slide-bar.

The slide-bar el, near its inner end, is provided with a pawl controller, 1S, made, as ,herein shown, of wire and secured to the slidebar by a screw, 19. The slide-bar cL is normally held with its cud extended through the guide 21 and so as to strike against the arm el as the last side of the button-hole is stitched to its small end. The slot c:s permits lost motion between the slide-bar and the screw c" of the pawl-carrier, andthe screw 15 determines how much of this lostv motion shall be permitted.

Now, when the pawl-carrier is moved backward or away from the clamp G the screw c", striking one end of the slot c, draws the slidebar c2 back with it against the spring 17; but as soon as the direction of movement of the lever b3 and pawl-earrier is reversed, should the movement of the slidesbar be checked in the least, so as not to respond to the spring 17-as, for instance, by the end of the said slide-bar meeting the arm c'l-then the pawlcarrier will have a slight movement while the slide-bar c2 and pawl-controller 18 remain at rest, and as a result thereof the pawl is permitted to turn on its pivot and engage one of the teeth 22 at the edge of the holding-bar44, and the latter bar will be moved by the pawl bl during the remainder of its stroke, and as the pawl so engages the holding-bar the screw 15 strikes the end of the slide-bar, and there-- after for the remaining stroke of the pawlcar rier bl and pawl the slide-bar is moved positively, and, by its outer cud against; the arm cl, vibrates the clamp C for a short distance about its pin 2 and against the stress of the usual spring, 7L, which carries the roll h.

The number of teeth at the edge ofthe holdingbar 44 equals the maximum number of stitches which it is desired to make to `finish or bar the end of the button-hole.

The screw 24 in a lug, 25, of the holding bar 44 may be turned to adjust the position of the bar and its teeth with relation to the pawl bl, so that the whole number of teeth may be engaged one after the other by the said pawl; or the bar may be so adjusted that less than the whole number of teeth maybe engaged before the end of the said bar 44,outside the bedplate A, will be withdrawn from below the foot D5 of the lever D, to thereby permit the spring 53 to turn the said lever on the ful Crum-pin Dz and cause the removal of the periphery of the pulley A5 from contact with thc periphery of the pulley A" and permit the brake-shoe 51, carried by the said lever, to meet the pulley Aland stop the rotation of the needle-bar-moving shaft Ail.

The screw 24 bears against the screw 26,ex tended through the slot 27 of the holding-bar, and by turning in the said screw 24 the num ber of teeth 22 which must be engaged by the pawl bl, one after the other, before the holding-bar is pulled from under the foot D5 is lessened. 44, prevents movement of the latter except it is positively drawn by the pawl.

The base C of the clamp will be provided with clamping-jaws and devices substantially such as commonly used in the Union buttonhole machines or clampingjaws substantially such as shown in the patent referred to.

The clamp-base C is made to travel in usual manner against the usual needle throat-piece, a, as a guide and to permit the clamp to be moved laterally when occupying the position shown in Fig. 1 by the action of the slidebar cl against the rigid arm cl of the clampbase. I have provided the under side of the said clamp-base at one side its straight slot with a slide block or plate, n', fitted into the under side of the clamp-base and flush with its under side, the said block or plate having a slot, al, which is entered by a pin, al', in the base.

By means of the block n, the clamp C, when the bar cZ meets the arm c2, as in Fig. 1, is permitted to move laterally at a point opposite the stationary throat-piece attached to the cover B.

I claim 1. The clamp-base C,provided with the arm or projection, the slide-bar to cooperate with and vibrate the said clamp, its pawl-controller, and the pawlcarrying slide and its pawl, combined with the bar 44,provided with teeth to be engaged by the said pawl, the number of teeth engaged by the pawl determining the number of stitches made in the barring, substantially as described.

The foot, by its friction on the bar IOO 2. The clamp-base C, provided with the arm or projection, the slide-bar to co-operate With and vibrate the said clamp,its paWl-controller, and the pawl-carrying slide and its pawl,con1 bined with the holding-bar provided with a series of teeth to be operated by the said pawl and with means to adj ust the range of movement of the said holding-bar according to the combined with a lever to move the said pawlcarrying slide-bar, the adjustment of the screw 15 varying the extent of vibration of the clamp, substantially as described.

4. The plate B, its stationary throat, and

the clamp-base provided with the loose block or plate n and the arm e", combined with the slide-bar and means to reciprocate it to vibratev the clamp, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

A. LINCOLN COOMBS.

Vitnesses:

G. W. GREGORY, F. CUTTER. 

